The present invention relates to a method of using fuel in an engine and more particularly to a fuel having a flash point over 5xc2x0 F. and the method of igniting the fuel in the cylinders of the engine.
The gasoline internal combustion engine is designed to utilize a fuel with a flash point of approximately xe2x88x9240xc2x0 F. to xe2x88x9250xc2x0 F. The fuel is mixed with air in a carburetor and passed to the cylinder, or is introduced by an injector into the cylinder, where a spark plug is timed to generate a spark to ignite the fuel/air mixture. Other engines such as diesel engines and jet airplane engines use a fuel with a higher flash point of up to 150xc2x0 F. The low flash point of gasoline is a major source of approximately 10,000 automobile fires per year in the United States. Also, gasoline contributes significantly to atmospheric pollution while the gasoline is being pumped into the fuel tank.
The ability to use fuels having a flash point of at least 100xc2x0 with internal combustion engines would provide significant economical and environmental benefits. Starting at the refinery, producers would not need to fractionate the crude petroleum to the same extent. This would result in savings in cost to the refiner. There would be fewer types of fuel required and the need for storage of many different fuels would be reduced. A single fuel would be available for a broad spectrum of vehicles and engines. There would be fewer fires and consequently there would be fewer human injuries and insurance costs could be reduced.
In order to use this fuel, the operation of the internal combustion engine can be changed and controlled. Also, redesigned electrodes, more efficient for the fuel are desired.
It is an object of the present invention to provide a method wherein fuel with a flash point of at least 50xc2x0 F. can be used in an internal combustion engine.
It is a further object of the present invention to provide a method for controlling the heating of cylinders within an internal combustion engine and for introducing into each heated cylinder a fuel having a flash point of at least 5xc2x0 F.
It is another object of the present invention to provide a method of controlling the introduction of fuel within the cylinder to more effectively use the fuel.
It is still another object of the invention to provide an electrode for a spark plug which is more effective with the fuel.
In accordance with the teachings of the present invention, there is disclosed a method of operating an internal combustion engine having a plurality of cylinders. Each cylinder has therein a respective spark plug having a pair of electrodes and a respective piston. The piston in each cylinder moves axially in a stroke. The stroke has a top position proximal to the respective electrodes and a bottom position distal from the respective electrodes. The internal combustion engine uses a petroleum based fuel having a flash point of at least 5xc2x0 F. A control means is provided attached to the engine. The control means controls the energizing of the electrodes in the spark plugs wherein the electrodes may be energized on a continuous basis or on an intermittent basis. The control means further controls the introduction of fuel into the cylinders. The electrodes of all of the spark plugs are energized continuously by the control means until the electrodes are heated to a temperature greater than the flash point of the fuel. Fuel as introduced into the respective cylinders by the control means when the respective piston is approximately at the top of the stroke such that the fuel ignites and forces the respective piston to the bottom of the stroke. In this manner, the engine is started. The electrodes of the respective spark plugs are energized intermittently by the control means on a timing basis. Fuel is introduced into the respective cylinders by the control means in a predetermined sequence, wherein the fuel in the respective cylinders is ignited by the intermittent firing of the electrodes to operate the engine. The fuel is continued to be introduced into the respective cylinders in a desired sequence and the respective electrodes are continued to be energized sequentially, wherein the engine operates normally using the fuel.
Further in accordance with the teaching of the present invention, there is disclosed electrodes for use in a spark plug in a cylinder in an internal combustion engine. Each electrode has an electrical conducting element which is energized to produce a spark. A heating element is juxtapositioned to the conducting element. A means is provided for heating the heating element separately from the electrical conducting element, wherein the heating element may be heated to a desired temperature and the heating may be discontinued. Fuel in the cylinder is initially heated by the heating element in the immediate vicinity of the electrical conducting element such that the heated fuel is more rapidly ignited when the electrical conducting element is energized to produce the spark.
These and other objects of the present invention will become apparent from a reading of the following specification taken in conjunction with the enclosed drawings.